usrp - In gnuradio, how much work is done in the fpga? -

some of these ettus boxes have serious (& expensive) fpga's in them. seems waste if pass data adc ethernet bus. when build in grc how signal processing done in fpga & how done pc?

gnu radio host software. so, processing program in gnu radio done on cpus, unless use special hardware accelerator blocks, example:

• gr-theano: gpu accelleration
• gr-fosphor: opencl-accelerated waterfall spectrogram
• gr-ettus: employing rfnoc implement specific functionality on x3x0's fpga. requires build fpga image including functionality use gr-ettus block.

generally, fpga in x3x0 lot: physically, adc , dac of x3x0 running @ 200mhz default, , can select integer fractions of "user sampling rate"; interpolation/decimation from/to rate match these hardware clocks done in fpga relatively large filters. also, can digitally shift signal in frequency setting digital tuning offset, done cordic in fpga.